SPRUCING up your garden could be the worst way to invest cash when it comes to adding value to your home.

While the popularity of TV gardening shows continues to grow, viewers gaining inspiration from Charlie Dimmock and Diarmuid Gavin stand to make huge financial losses, warns James Duffell, of The One Account - the current account mortgage provider owned by the Royal Bank of Scotland.

A garden makeover can cost up to £6,000, but homeowners will see the value of their property rise by only 10 per cent of their outlay, according to the company's valuation experts.

Central heating and double glazing also perform poorly. A new heating system costs between £3,000 and £6,000, while fitting double glazing costs between £4,000 and £15,000.

Meanwhile the property's value is likely to increase by only a quarter of the cost of installation in each case.

Building a garage or an off-road parking bay is the top investment to increase your property's worth.

A garage costs between £15,000 and £40,000 to erect, but the outlay is likely to be recouped in full. Loft conversions cost £15,000-£30,000 are likely to recoup at least 75 per cent of outlay.

But despite some improvements proving to be a better investment than others there are no magic formulae to increasing the value of your home, warns Duffell.